Combustion apparatus



Ap 1, 1941. jJ. E. McADAMs ouusnon `APPARATUS Filed June 30, 1,959

Patented Apr. l, 1941 COMBUSTION APIABATUS J haus s om,`

o''elpesedamapringdeld, oalaigno teel Producti r to Company,

Springeld, Ohio. a corporation of Ohio Application June 30, 1939, Serial No. 282,107

' 9 claim. (ci. lss-5s) 'I'his invention relates to heating apparatus and more particularly to fuel feeding and stoking apparatus for furnaces and the like.

A principal object of the invention is the provision of a power driven fuel feeding and stokingvapparatus which is of relatively simple and inexpensive construction and which provides for feeding the fuel from a hopper or the like positioned in spaced relation with respect to the fuel feed opening of the furnace to provide for free opening of the fire doors and to permit access to the re bed for the purpose of cleaning the re retort and attending to the re.

A further object is the provision of such apparatus in which the feeding of the fuel froin the hopper is automatically controlled to supply fuel to the furnace as required and to avoid objectionable packing and crushing of the fuel,v

thereby` overcoming undue strain and binding of the feeding apparatus.

A still further object is to provide a combined fuel feeding and stoking apparatus in which a rotary conveyor provides for feeding fuel from a hopper into position to be received by a ram and delivered thereby to a retort with the rotary conveyor feeding only so much fuel to the ram as will be received therein without packing or crushing of the fuel.

Other objects and advantages will be apparent from the following description, the appended claims and the attached drawing, in which:

Fig. 1 is a part section and part plan view taken on the line l-I of Fig. 2 and showing a portion of a boiler furnace provided with a fuel feeding and stoking apparatus constructed in accordance with the present invention; and

Fig. 2 is a vertical sectional view of the boiler furnace and fuel feeding and stoking apparatus taken substantially centrally of the feeding and stoking apparatus with certain parts shown in elevation.

Referring to the drawing which illustrates a preferred embodiment of the invention there is shown/ a furnace I which may be of any desired/or conventional construction and comprises a front furnace wall il, a fire door i2, a retort I3 of suitable construction and an opening I4 for supplying fuel to the retort. 'I'he fire door I2 provides for access to the top of the fire bed for the purpose of attending to theilre, cleaning out the retort, etc.

A hopper' or the like for receiving a quantity of solid fuel such as coal, coke,A or the like and supplying the same to the retort of the furnace is indicated at 20, and as shown is positioned in radially outwardly.

spaced relation with the front wall of the door l2 at a distance sufficient to permit free opening' of the door l2 andready'access into the interior of the furnace for the Ypurposes hereinabove described. The hopper 20 comprises a substantially vertical front wall 2l and a pluralityof inwardly and downwardly sloping walls 22, 22an'd 24 providing for feedingthe fuel material received with- 'in the hopper towards an opening in the bottom thereof. The front wall 2l vanda portion of the side walls 22 and 2l are cut away adjacent the bottom of the hopper as indicated at 2B and 26 respectively to provide a lateral discharge opening in the lower portion of the hopper.

The rotary conveyor Il is mounted on a vertical axis positioned laterally .of the hopper 20 between the hopper and furnace Il and is adapted to enter the hopper through the lateral opening provided in the lower portion thereof to revceive a portion of the fuel contained in the hopper and feedit to a position adjacent the fuel inlet opening Il. As shown the rotary conveyor 30 comprises a central hub 3| and a plurality of vlat'erally extending arcuately spaced arms 32 reinforcedadjacent the outer ends by a reinforcing ring 33. As shown in Fig. 1 the arms are displaced from a radial position and rotation takes place in such direction as illustrated by the arrow that the arms move with a sweeping motion which tends to cause the fuel particles to move A substantially cylindrical housing comprising a top wall 35, a side wall 36 and a bottom wall 3l encloses the rotary conveyor 20 and the lateral opening in the lower A' portion of the hopper 20. As shown in Fig. 2

the bottom wall 3l of the conveyor housing extends entirely across the bottom of the hopper 20 and provides a closure for the open bottom thereof. The rotary conveyor 30 is journalled in the conveyor housing by means of a shouldered downwardly projecting portion 40 on the hub 3l which takes its bearing in a flanged opening provided in the bottom wall 31 and a vertically extending shaft 4l which is carried by the hub 3| and takes its bearing in a downwardly projecting boss l2 provided on the top member 35 of the conveyor housing. The spindle Il extends downwardly beyond the lower end of the shouldered portion III of the hub and carries a sprocket 43 which is keyed to the hub 2i by the elongated pins I4 and provides for driving the conveyor to effect the rotation thereof.

A quantity of the fuel within the hopper is received between the arms 32 of the rotary conveyor and is carried by the arms to a position adjacent the front of the fuel inlet opening ,Il of the furnace where it is discharged through an opening 41 provided in the bottom wall I'I of the conveyor housing. As above described the conveyor arms 32 are so disposed that asthe conveyor rotates to feed the fuel towards the furnace the fuel tends to move outwardly towards the periphery of the convey'or housing and will thus be readily discharged from the conveyor by dropping through the discharge opening 41. The side wall 3l ofthe conveyor housing slopes outwardly and downwardly as shown to facilitate the discharge of the fuel through the opening l1, and the ends of arms l2 approach closely and are correspondingly tapered to avoid escape of fuel around the ends thereof during the feeding movement. To avoid unnecessary grinding or crushing of the fuel as the feeding rotor turns a spacing is provided between the tops of the arms l! and the top plate ll of the enclosing housing, and if desired a similar spacing may be provided between the bottom of the arms I! and the bottom plate l1.

The bottom wall 314 of the conveyor housing is provided with a downwardly extending flange Il surrounding the discharge opening "and thetopwallofaramcasing Ilisintegrally attached to .the lower end of the flange I8. The flange ll thus provides a spacing between the bottom wall 31 of the conveyor homing and the top wall Il of the ram casing Il with-ln which the driving sprocket I3 for the conveyor is positioned. The ram casing 50 extends outwardly beyond the hopper 2l at the end remote from the furnace Il and is provided at this end witha top plate 5I having an upwardly extending portion i2 which is reinforced by webs and provides a bracket for supporting the power drive means for the feeding and stoking mechanism. The casing Il is arranged in alignment with the fuel inlet opening of the retort I3 and is provided adjacent the furnace with forwardly extended side walk I5 and bottom wall which are received within the fuel inlet opening Il and are supported on a flanged ledge 51 provided on the iower front wall il of the furnace. A pedestal Il supports the casing 5I at its end remote from the furnace. v

The ram casing il thus provides a. chamber which is positioned below the discharge opening l1 of the conveyor 3l in alignment with the inlet opening of :the retort I3 and is adapted to receive the fuel which is discharged through the opening 41. As shown in F1322 the upper surfaceof thebottomwallllof-theramcasing lies in the same plane as the upper surface of the botwm I i of the retort Ito provide for the free feeding of the fuel from the interior of the ram casing into the retort.

A ram Il is-slidably. mounted within the ram casing il and .provides for intermittently feeding fuel which is received within the ram casing from the conveyor 3l into the retort I3. The ram 8l comprises a hollow casting provided with a downwardly and forwardly sloping front face II, a lower bearing slide block l2 and a pair of inwardly extending bosses il and Il. A oonnectlngrodpinilismountedwithinthebosses and M and provides for operatively connectingtheramllwithaconnectingrodll which entends longitudinally of the casing 5l and provides for eifecting intermittent reciprocation of A common power means is provided for effecting the rotation of the feed conveyor 3l and aasaeoi reciprocartion of the staking ram SII. As shown a gear casing 1I is mounted on the upstanding bracket n and supports an electric motor 1I which is opemtively connected with the gearing within the gear casing by means of a V-belt 12 and a pair of sheaves 1! and 14 mounted on the motor shaft and the gear casing respectivefly. Suitable reduction gearing controlled by clutch lever Ilgisprovided within the casing 'Il and :providesa drive for a' vertically extending drive shaft 1t which proiects outwardly from the bottom of 'the gear casing. A crank 11 is keyed to the lower end of the drive shaft 18 and a. driving sprocket 1i is mounted on the shaft 16 above the crank 11 and is secured to rthe crank for rotation therewith by a plurality of elongated pins 1l.

Roller chain l2 connects the sprocket 1l pro-l vided on the drive shaft 'Il with the sprocket Il provided on the hub -3I of the rotary feed conveyor and provides for effecting rotation of the conveyor whenever the driving motor 1I is put .into operation. The sprocket chain I2 extends within the spacing provided between the bottom I1 of the conveyor housing and the top 4! of the ram casing and is protected from the fuel within the hopper and conveyor by the bottom member 31 which closes the bottom of the hopper and the conveyor. A sheet metal housing O3 covers the portion of the sprocket chain I! which is not enclosed by the bottom 31 of the conveyor housing and top I! of the ram casing and provides a further protection f-or the sprocket chain.

The crank arm 11 which is mounted on the lower en d of the drive shaft 'Ii is operatively connected with the connecting rod GI to effect the reciprocation of the ram ill by means of a sliding lost-motion connection which provides a dwell in the movement of the ram after each forward and return stroke. This connection comprises a sleeve Il which is pivotally connected to the crank 11 and is siidably received on the oonnecbing rod between a fixed collar and an adjustable sleeve l1. Outward movement of the sleeve l1 towards the end of the connecting rod 88 is limited by a stop nut 88 which is threaded on the end of the connecting .-rod and provides for adjusting the spacing between the sleeve l1 and the fixed collar I6. From -the foregoing description ift will be evident that as the crank I1 ro. tates the sleeve 8S will slide on the connecting rod between the sleeve 81 and collar I8 and the ram Il will remain stationary until the sleeve I has moved into engagement with collar. I6, after which the ram will bamoved in a. forward feeding direction until the crank reaches the end of its forward stroke. The ram will then ll and the adjmtable collar 81 making 4it possible to vary the time of dwell of the ram or to eliminate the dwell entirely if desired.

In the operation of the device the drive motor 1I is energized and causes the rotation of the rotary conveyor 3! to continuouslyfeed fuel from the interior of the hopper 20 to the discharge opening 4l provided adjacent the front of the furnace. The fuel thus fed drops through the discharge opening into the chamber provided by the ram casing and is intermittentlyadvanced into the retort I3 through the opening Il by the reciprocatory movement of the ram l0. During the forward stroke of the ram the top portion thereof serves as a wall preventing the passage of any of the fuel into the portion of the ram casing in the rear of the ram. .The dwell of the ram after each stroke thereof provides for the feeding of a. sufficient quantity of new fuel to replace that which has been fed into the fire box by the ram.

If the rotary conveyor feeds more material than is being fed into the furnace by the ram the excess fuel does not discharge through the opening 41 but is merely carried around with the arms 32 as they rotate towards the hopper 20, thus avoiding objectionable packing or crushing of the fuel within the ram casing and any strain or binding in the parts of the feed rotor. During the subsequent movement of the arms 32 within the feed hopper only such additional material will be picked up as will be carried between the arms. The feeding of the fuel is thus automatically controlled by theA construction and operation of the rotary conveyor itselfand without the necessity for any special operation on the part of an operator or any special mechanism connecting with thepower drive so that proper feeding action is secured at all times and throughout the range of adjustment of the stroke of the ram.

The present invention is of particular advantage in the case of relatively `small stokers applied to fire box type steel boilers. There are many installations of such boilers in which the stoker cannot be so positioned as to make it possible to locate firing doors beneath the water'leg of the boiler. It is common practice in such cases, therefore, to use the `ring doors of the boiler for the purpose of attending the re and cleaning the fire box. In accordance with the present invention the hopper may be spaced sufficiently far from the boiler to permit free opening of the boiler firing doors and ready access to the fire bed of the boiler re box, and a relatively simple, inexpensive and highly effective means is provided for conveying the fuel from the hopper to the furnace and-feeding it into the re box.

While the form of apparatus herein described constitutes a preferred embodiment of the inven. tion, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A fuel feeding apparatus of the character described for feeding solid fuel to a retort comprising a hopper adapted to receive a quantity of solid fuel, rotary feeding means adapted to enter said hopper through an opening in the lower part thereof for receiving fuel from said hopper and discharging said fuel at a position spaced laterally from said hopper, said rotary feeding means comprising a plurality of arms mounted for rotation about a substantially vertical axis and having open vertically extending passages therebetween through which fuel received from said hopper is adapted to move downwardly under the action of gravity in a generally axial direction, a housing overlying said rotary feeding means, the upper surface of said arms. being spaced below the walls of said. housing and of said hopper to provide a clearancespacefor preventing crushing of th fuel therebetween, a bottom wall for said housing having an aperture therein spaced from said hopper and in line with the path traversed by said arms to discharge fuel downwardly from between said arms, and additional means positioned below said discharge opening for receiving the fuel discharged through said opening and for feeding the same into a retort, said rotary feeding means providing for discharging through said aperture only such quantity of fuel as removed by said additional feeding means while -retaining the remainder therein without substantially packing or crushing thereof.

2. A fuel feeding apparatus of the character described for supplying solid fuel to a retort having a door providing for access thereto comprising a hopper spaced away from said door and adapted to receive a quantity of solid fuel, rotary feed means adapted toenter said hopper through an opening in the lower part thereof for receiving fuel from said hopper and discharging said fuel at a position spaced from saidl hopper, said feed means being rotatable about a substantially vertical axis positioned laterally of said hopper and toward said retort so that fuel ilows into said rotary feed means in a generally axial direction and intermediate the axis and the outer periphery thereof, a generally cylindrical housing communicating with the lowermost portion of said hopper on the side toward said retort in which said rotary feed means rotates, said housing having an upper wall positioned adjacent but below the level of said door to avoid obstructing access thereto and having a lower wall which is p rovided with van opening therein adjacent said retort, said rotary feed means comprising a plurality of arms having spaces therebetween and rotatable over said lower wall and said opening to provide for downward movement of the fuel in a generally axial direction under the action of gravity through the spaces between said arms when said spaces are brought into discharge position above said opening, a chamber positioned below said rotary feed means for receiving fuel discharged therefrom, and means movable within said chamber for advancing fuel received therein to a retort or the like, said rotary feed means providing for discharging only such quantity of fuel as will be freely received within said,

chamber while avoiding substantialpacking or crushing of the fuel therein.

3. A fuel feeding apparatus of the character described comprising an upwardly extending hopper, a conveyor housing communicating with said hopper at the lowermost portionlthereof and having its major portion'extending laterally beyond the projected area of said hopper and having a substantially fiat bottom wall provided with a discharge opening located in a position spaced from the hopper, rotary conveyor means mounted for rotation about a substantially vertical axis within said conveyor housing and comprising a plurality of outwardly extending arms with spaces therebetween providing for receiving fuel under the action of gravity by movement in a generally axial direction from said hopper and feeding it downwardly through said bottom dis charge opening, a chamber positioned below said discharge opening of thev conveyor housing for receiving fuel discharged therethrough, means for rotating said Vconveyor means to effect continuous feeding of fuel towards said discharge opening, and means in said chamber for feeding fuel received therein to a retort or the like, and means for effecting intermittent operation of said retort feeding means, said rotary conveyor means providing for discharging'only such quantity of fuel as will freely. fall through said dischargeA opening into said chamber therebelow in accordance with the rate of feed of said intermittently operated retort feeding means, and said hopper in cooperation with said conveyor means providing for supplying only .such additional quantity of fuel to the conveyor means as has been discharged from the conveyor means through said discharge opening.

4. A fuel feeding apparatus of the character described which comprises a fuel hopper provided with a lower discharge outlet, a rotary feeding member mounted on an axis positioned laterally of said hopper, said feeding member comprising a plurality of laterally extending non-radial arcuately spaced arms each having a substantial depth in a plane substantially perpendicular to the direction of rotation thereof and adapted to rotate within said hopper outlet to receive fuel from the hopper, a housing for enclosing said feeding member, said housing having an opening providing for the discharge of fuel fed by said arms at a position spaced from said hopper, means for rotating said feeding member to effect the feeding of said fuel from said hopper to said discharge opening, a chamber positioned below said discharge opening for receiving the fuel discharged therethrough, and means including a reciprocating ram in said chamber for feeding fuel received therein forwardly, said arms of the rotary feeding member providing for discharging only such quantity of fuel as will freely fall through said discharge opening into said chamber therebelow in accordance with the rate of feed of said ram and for withdrawing fuel not discharged away from the discharge opening.

5. A fuel feeding apparatus of the character described which comprises a fuel hopper provided with a lower discharge outlet, a rotary feeding member mounted on an axis positioned laterally of said hopper, said feeding member comprising a plurality of laterally non-radially extending arcuately spaced arms each having a substantial depth in a plane substantially perpendicular to the direction of rotation thereof and adapted to rotate within said hopper outlet to receive fuel from the hopper and to carry it in an arcuate path and with a sweeping motion causing the fuel to move radially outwardly thereof, a housing for enclosing said feeding member, said housing having an opening providing for the discharge of fuel fed by said arms at a position spaced from said hopper, means for rotating said feeding member to eifect the feeding of said fuel from said hopper to said discharge opening, a chamber positioned below said discharge' opening for receiving the fuel discharged therethrough, and means including a reciprocating ram in said chamber for feeding fuel received therein forwardly, said arms of the rotary feeding member providing for discharging only such quantity of fuel as will freely fall through said discharge opening into said chamber therebelow in accordance with the rate of feed of said ram and for withdrawing fuel not discharged away from the discharge opening.

6. A fuel feeding apparatus of the character described which comprises a fuel hopper provided with a lower discharge outlet, a rotary feeding member mounted on a substantially vertical axis positioned laterally of said hopper, said feeding member comprising a plurality of laterally extending non-radial arcuately spaced arms each having substantial depth in a substantially vertical plane and adapted to rotate within said hopper outlet to receive fuel from the hopper, a housing for enclosing said feeding member, said housing having a bottom opening providing for the discharge of fuel fed by said arms at a position spaced from said hopper, means for rotating said feeding member to effect the feeding of said fuel from said hopper to, said discharge opening, a chamber positioned below said discharge opening for receiving fuel discharged therethrough, a reciprocatory ram positioned in said chamber for feeding fuel received therein forwardly, and means for effecting intermittent reciprocation of said ram, said arms of the rotary feeding member providing for discharging only such quantity of fuel as will freely fall through said discharge opening into said chamber therebelow in accordance with the rate of feed of said ram and for withdrawing fuel not discharged away from the discharge opening.

7. A fuel feeding apparatus of the character described which comprises a fuel hopper provided with side walls and a lower discharge outlet, a rotary feeding member mounted on a substantially vertical axis spaced laterally of said side walls of the hopper, said feeding member comprising a plurality of laterally extending arcuately spaced arms each having substantial depth in a vertical plane and adapted to rotate within said hopper outlet at the bottom of said hopper to receive fuel from said hopper by movement thereof under the action of gravity under a generally axial direction into the spaces between said arms as required to fill the same, a housing for enclosing said feeding member extending laterally of said hopper at approximately the level of the outlet therein, said housing having a bottom opening providing for the gravity discharge of fuel fed by said arms at a position spaced from said hopper, a chamber positioned below said discharge opening for receiving fuel discharged therethrough, a ram slidable within said chamber for feeding fuel received therein forwardly, common drive means for effecting reciprocating movement of said ram and for rotating said feeding member to eifect the continuous feeding of said fuel from said hopper to said discharge opening, and means for adjusting the rate of feed of said ram independently of said rotary feeding member to effect controlled supply of fuel, said arms of the rotary feed member providing for discharging only such quantity of fuel as will freely fall through said discharge opening into said chamber therebelow in accordance with the rate of feed of said ram and for withdrawing fuel not discharged away from the discharge opening.

8. A fuel feeding apparatus as defined in claim 2 in which the means movable within the chamber for advancing fuel received therein to the retort or the like comprises a reciprocable ram slidably mounted in said chamber.

9. A fuel feeding apparatus as defined in claim 2 including means for continuously operating the rotary feed means, and additional means for intermittently operating the means movable within the chamber for advancing fuel received therein to the retort or the like.

JOSEPH E. McADAMS. 

